Visitors to Koh Chang can no longer feed the monkeys that live on the island or they risk being fined THB500 each.

Though warning signs against feeding the monkeys have long stood, in both English and Thai, in the areas where the wild monkeys congregate, conservation officials decided to introduce the fine because tourists were not obeying and continued to feel the monkeys, mostly of the long-tailed macaque variety.

Though the monkeys naturally forage for food in the woods, being hand-fed by tourists for generations has made them spoiled. It’s for this reason that they no longer like to forage and, when tourists don’t feed them, they turn aggressive and attack visitors or rob food vendors for their meals, reported Thai PBS.

It’s common on the island to see the monkeys lined up along the street just waiting for some tasty treats from tourists hoping to get the perfect naughty monkey selfie.